The present invention relates to swimming pool filtration generally and to canister filters in particular.
The technology for maintaining the clarity and cleanliness of swimming pool water has developed significantly over the past 50 years. Currently, most new pools have at least three filters. There is a first filter for removing fine, suspended particulate such as dust and bacteria. This filter may is typically a tank containing sand or diatomaceous earth. There is a second filter for capturing floating debris, such as leaves and twigs. This second filter is often referred to as a skimmer because it is located along the side of the pool where it skims this floating debris to readily separate it from the water using a coarse mesh basket.
Typically, swimming pools also have a third filter, called a canister filter, for capturing sediment and heavier debris, such as water-logged leaves, from the bottom of the pool. This filter is positioned in line between the main drains of the pool, commonly located near the lowest point in the pool, and the suction side of the pump that delivers the pool water to the first filter.
The canister filter contains a strainer or fine-mesh, bag-like sieve to trap sediment and thus allow its removal periodically by the pool caretaker.
As the number of residential pools has increased, so, too, has the design of residential pools evolved to become larger and more customized. The residential owner demands that the pool require less maintenance and either be self-cleaning or have systems that make it easier to clean. Skimmers and suspended matter filters generally do a good job of removing floating and suspended debris and dirt. Sediment, however, requires more effort. Consequently, additional floor drains, pop-up cleaning jets built into the walls and floor of the pool, and robotic cleaners have been developed to facilitate the sweeping or vacuuming of sediment from the pool floor to the return lines. However, there remains a need for a better way to keep pools clean, and to manage sediment collection better.